Here the GTX 280 takes a healthy, near 20 FPS lead over the Palit HD 4870 Sonic at 1280x1024, but this lead is all but disintegrated when the resolution is set to 1920x1440.
When compared to the stock-clock VisionTek HD 4870, the Palit HD 4870 Sonic gains about 5 FPS across the three resolutions.